Retardation film and a liquid-crystal display device comprising the same

Abstract

The present invention relates to a retardation film that comprises a blend resin of 1) an acryl-based copolymer resin that comprises an alkyl methacrylate-based monomer and a cycloalkyl methacrylate-based monomer, and 2) a resin that comprises an aromatic ring or aliphatic ring in a polymer main chain, a method for manufacturing the retardation film, and a liquid crystal display device that comprises the retardation film. The retardation film according to the present invention has excellent heat resistance, optical transparency, mechanical strength, and durability.

Description

[0001]This application is a National Stage Entry of International Application No. PCT / KR2009 / 007036, filed on Nov. 27, 2009 and claims the benefit of Korean Patent Application No. 10-2008-0119610, filed on Nov. 28, 2008, which is incorporated herein by reference in its entirety.TECHNICAL FIELD[0002]The present invention provides a retardation film that has excellent heat resistance and optical transparency, low haze, is not easily broken, and has excellent mechanical strength and durability, a method for manufacturing the same, and a liquid crystal display device comprising the retardation film.[0003]This application claims priority from Korean Patent Application No. 10-2008-0119610 filed on Nov. 28, 2008 in the KIPO, the disclosure of which is incorporated herein by reference in its entirety.BACKGROUND ART[0004]Recently, display technologies using various methods such as a plasma display panel (PDP), a liquid crystal display (LCD) and the like that are used instead of a known brown...

AI Technical Summary

Benefits of technology

[0014]In a retardation film according to the present invention, an optical property is excellent, optical transparency is excellent, and mechanical properties, processability, heat resistance, and retardation implement property are excellent. In addition, the optical film according to the present invention is characterized in that it has a low photoelastic coefficient in comparison with a known retardation film, polarizer protective film, for example, TAC film.BEST MODE

[0015]A retardation film according to the present invention comprises a blend resin of 1) an acryl-based copolymer resin that comprises an alkyl methacrylate-based monomer and a cycloalkyl methacrylate-based monomer, and 2) a resin that comprises an aromatic ring or aliphatic ring in a polymer main chain.

[0016]In the retardation film according to the present invention, the alkyl group of the alkyl methacrylate-based monomer of 1) has preferably 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms, and much more preferably methyl group or ethyl group. As detailed examples of the alkyl methacrylate-based monomer, there are methyl methacrylate, ethyl methacrylate and the like, it is more preferable to use methyl methacrylate, but they are not limited thereto.

[0017]In the retardation film according to the present invention, it is more preferable that the cycloalkyl methacrylate-based monomer of 1) is cyclohexyl methacrylate, but it is not limited thereto.

[0018]In the retardation film according to the present invention, the contents of the alkyl methacrylate-based monomer and cycloalkyl methacrylate-based monomer in 1) acryl-based copolymer resin may be selected from the range of 0.1 to 99.9 wt %, respectively. In particular, the alkyl methacrylate-based monomer is preferably in the range of 70 to 99.9 wt % and the cycloalkyl methacrylate-based monomer is preferably in the range of 0.1 to 30 wt %, but they are not limited thereto.

[0019]1) the acryl-based copolymer resin may further comprise the styrene-based monomer such as styrene, alpha-methyl styrene.

Problems solved by technology

For example, in the case of the liquid crystal display, according to the development toward the thin film, the lightness, and enlargement of the screen area, the wide viewing angle, the high contrast, the suppression of change in image color tone according to the viewing angle and the uniformity of the screen display are particularly considered as important problems.

In addition, light does not pass through the front sides of two polarizing plates that are vertical to each other, but if the angle is inclined, the light axes of two polarizing plates are not vertical to each other, thus light leakage occurs.